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United States Patent |
5,321,671
|
Yoshida
|
June 14, 1994
|
Radio receiver with tape deck having interrupt capability
Abstract
Occurrence of mechanical noise and tape damage due to operation of a pinch
roller is avoided when the system is switched from the tape playback mode
to the radio mode or vice versa. On playback of the tape, an interrupt
signal 33 from a microcomputer 34 is low. Transistors 28 and 13 are thus
turned on. A drive motor 14 in the tape deck 11 is energized by power from
a (+B) terminal 45. When the cassette tape is loaded into the tape deck, a
plunger 15 is energized directly by power from a (TAPE+B) terminal 12.
Thus, a pinch roller 41 in a head drive mechanism 16 is brought into
contact with the tape 43. If the microcomputer 34 detects any interrupt
signal such as traffic or emergency information signals multiplexed with
FM broadcasting waves, it changes the interrupt signal to high so that the
transistors 28 and 13 are turned off. Therefore, the drive motor 14 is
de-energized, but the power continues to be supplied to the plunger 15.
Consequently, the pinch roller 41 and the tape 43 will be maintained in
contact with each other and will not influenced by the switching between
the tape and radio modes.
Inventors:
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Yoshida; Shigehiro (Sanda, JP)
|
Assignee:
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Mitsubishi Denki Kabushiki Kaisha (Tokyo, JP)
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Appl. No.:
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919236 |
Filed:
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July 27, 1992 |
Foreign Application Priority Data
Current U.S. Class: |
369/6; 360/137; 369/2; 369/10; 381/86 |
Intern'l Class: |
H04B 001/20 |
Field of Search: |
369/6,10,31,2
381/86
360/1,137
|
References Cited
U.S. Patent Documents
5073943 | Dec., 1991 | Chapman | 381/86.
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Foreign Patent Documents |
1-93689 | Jun., 1989 | JP.
| |
Other References
R. Laugisch; Zwei Empfanger in einem Gerat--das neue Grundig
Cassetten-Autoradio WKC 2960 VD Infomat; 1985, Issue 2/3, pp. 99-108.
|
Primary Examiner: Pascal; Robert J.
Assistant Examiner: Ratliff; Reginald A.
Claims
I claim:
1. A radio receiver with tape deck, comprising:
a tape deck having:
(a) a drive motor for driving a cassette tape;
(b) a roller-capstan mechanism including a pinch roller and a capstan, said
mechanism being adapted to guide the cassette tape nipped between said
pinch roller and capstan on recording and reproducing of audio signals to
and from a cassette tape;
(c) a head brought into contact with the tape to record and reproduce the
audio signals when the tape is nipped between the pinch roller and the
capstan;
(d) a plunger for actuating a head holding latch to move the pinch roller
to a pinching-on state in which the tape is nipped between the pinch
roller and the capstan when said plunger is energized and for releasing
said head holding latch to move the pinch roller to a pinching-off state
in which the tape is released from between the pinch roller and the
capstan when said plunger is deenergized, and
said radio receiver further comprising:
(e) a radio receiving circuit for receiving broadcast waves including
interrupt signals such as traffic and emergency information signals;
(f) a demodulating circuit for demodulating the broadcast waves received by
said radio receiving circuit;
(g) an interrupt signal detecting circuit for detecting the interrupt
signal from the signals demodulated by said demodulating circuit;
(h) an output switching circuit for outputting radio voice signals from
said radio receiving circuit if any interrupt signals are detected by said
interrupt signal detecting circuit; and
(i) a first power terminal for supplying electric power to said plunger in
the event of a cassette tape being loaded into the tape deck,
irrespectively of the state of said output switching circuit.
2. A radio receiver with tape deck as defined in claim 1 wherein said
interrupt signal detecting circuit includes a microcomputer.
3. A radio receiver with tape deck, comprising:
a tape deck having:
(a) a drive motor for driving a cassette tape;
(b) a roller-capstan mechanism including a pinch roller and a capstan, said
mechanism being adapted to guide the cassette tape nipped between said
pinch roller and capstan on recording and reproducing of audio signals to
and from a cassette tape;
(c) a head brought into contact with the tape to record and reproduce the
audio signals when the tape is nipped between the pinch roller and the
capstan;
(d) a plunger for actuating a head holding latch to move the pinch roller
to a pinching-on state in which the tape is nipped between the pinch
roller and the capstan when said plunger is energized and for releasing
said head holding latch to move the pinch roller to a pinching-off state
in which the tape is released from between the pinch roller and the
capstan when said plunger is de-energized, and
said radio receiver further comprising:
(e) a radio receiving circuit for receiving broadcast waves including
interrupt signals such as traffic and emergency information signals;
(f) a demodulating circuit for demodulating the broadcast waves received by
said radio receiving circuit;
(g) an interrupt signal detecting circuit for detecting the interrupt
signal from the signals demodulated by said demodulating circuit;
(h) an output switching circuit for outputting radio voice signals from
said radio receiving circuit when audio playback signals are outputted
from said tape deck and if any interrupt signals are detected by said
interrupt signal detecting circuit; and
(i) a first power terminal for supplying electric power to said plunger in
the event of a cassette tape being loaded into the tape deck,
irrespectively of the state of said output switching circuit, wherein
a voltage is applied to said first power terminal only in the tape playback
mode when the tape is loaded into the tape deck.
4. A radio receiver with tape deck as defined in claim 3 wherein said drive
motor is energized by another electric power from a second power terminal
distinct from said first power terminal.
5. A radio receiver with tape deck as defined in claim 4 wherein said
second power terminal receives a voltage only when the tape is loaded into
said tape deck and if said interrupt signal is not detected by said
interrupt signal detecting circuit.
6. A radio receiver with tape deck as defined in claim 5, further
comprising (j) a first transistor maintained at its "OFF" state when there
is no interrupt detection signal from said interrupt signal detecting
circuit; (k) a second transistor turned on when said first transistor is
in its "OFF" state and the voltage is applied to said first power
terminal; and (l) a third transistor turned on when said second transistor
is turned on, whereby the power can be supplied from said second power
terminal to said drive motor when said third transistor is turned on.
7. A radio receiver in combination with a tape deck, comprising:
a tape deck including,
a drive motor for driving a cassette tape;
a pinch roller and a capstan adapted to guide the cassette tape nipped
between said pinch roller and capstan;
a head, brought into contact with the tape to reproduce audio signals;
plunger means for moving the pinch roller to nip the tape between the pinch
roller and the capstan when said plunger means is in an energized state
and for moving the pinch roller to release the tape from between the pinch
roller and the capstan when said plunger means is in a de-energized state,
and
a radio receiver including:
a radio receiving circuit for receiving broadcast signals including
interrupt signals;
a demodulating circuit for demodulating said broadcast signals;
an interrupt signal detecting circuit for detecting an interrupt signal
from the demodulated broadcast signals;
an output switching circuit for outputting radio signals derived from said
demodulated broadcast signals when said interrupt signal is detected by
said interrupt signal detecting circuit; wherein
said plunger means maintains said energized state when said output
switching circuit outputs said radio signals derived from said demodulated
broadcast signals.
8. The radio receiver in combination with a tape deck as defined in claim 7
wherein said interrupt signal detecting circuit includes a microcomputer.
9. The radio receiver in combination with a tape deck as defined in claim 7
wherein said plunger means is energized only when a tape is loaded into
said tape deck.
10. The radio receiver in combination with a tape deck as defined in claim
9 wherein said plunger and said drive motor are energized by first and
second power terminals respectively.
11. The radio receiver in combination with a tape deck as defined in claim
10 wherein said second power terminal receives a voltage only when a tape
is loaded into said tape deck and when said interrupt signal is not
detected by said interrupt signals detecting circuit.
12. The radio receiver in combination with a tape deck as defined in claim
11, further comprising a first transistor maintained at its "OFF" state
when there is no interrupt detection signal from said interrupt signal
detecting circuit; a second transistor turned on when said first
transistor is in its "OFF" state and voltage is applied to said first
power terminal; and a third transistor turned on when said second
transistor is turned on, whereby power is supplied from said second power
terminal to said drive motor when said third transistor is turned on.
13. A method for operating a radio receiver in combination with a tape
deck, the tape deck including a drive motor, a pinch roller, a capstan, a
head, and a plunger, the method comprising:
(a) receiving broadcast signals including interrupt signals;
(b) demodulating said broadcast signals;
(c) detecting an interrupt signal from the demodulated broadcast signals;
(d) driving a cassette tape with said drive motor;
(e) guiding said tape between said pinch roller and said capstan;
(f) contacting said tape with said head to reproduce audio signals;
(g) energizing the plunger to move the pinch roller to nip the tape between
the pinch roller and the capstan;
(h) maintaining energizing said plunger when said interrupt signal is
detected in step (c); and
(i) outputting radio signals derived from said demodulated broadcast
signals when said interrupt signal is detected in step (c).
14. The method of claim 13 further including the step of loading a tape
into said tape deck; and step (g) and step (h) are performed only when
said tape is loaded into said tape deck.
15. An apparatus for operating a radio and tape player comprising:
a drive motor for driving a tape;
a pinch roller and a capstan for guiding the tape; a head;
means for receiving broadcast signals including interrupt signals;
detecting means for demodulating the broadcast signals;
detecting means for detecting an interrupt signal from the demodulated
broadcast signals;
means for contacting the tape with said head to reproduce audio signals;
moving means for moving said pinch roller to nip the tape between said
pinch roller and said capstan and for maintaining the tape to be nipped
between said pinch roller and said capstan when the interrupt signal is
detected by said detecting means; and
means for outputting radio signals derived from the demodulated broadcast
signals when the interrupt signal is detected by said detecting means.
16. The apparatus of claim 15 further including means for determining
whether a tape is loaded into said tape deck and outputting an output
signal in response to the determination; and wherein
said moving means is responsive to the output signal.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention:
The present invention relates to a radio receiver and particularly to a
radio receiver containing a cassette tape deck therein.
2. Description of the Related Art:
Many car or domestic radio receivers include a cassette tape deck contained
therein so that a user can easily play back cassette tapes in addition to
radio broadcastings. Recently, multi-functional radio receivers have been
developed. For example, a radio receiving system has been now developed
which has a radio broadcasting interrupt function for offering a radio
broadcast announcing traffic or emergency information during the
playing-back of a tape, if necessary. This is accomplished by transmitting
broadcasting waves containing an interrupt signal which is multiplexed
with general broadcasting waves and by receiving and demodulating them
into the desired radio broadcast, in accordance with an FM multiplex
broadcasting technique such as RDS.
FIG. 2 is a block diagram illustrating the primary parts of a radio
receiver with a tape deck which is constructed in accordance with the
related art. The radio receiver comprises a tape deck 11 which is adapted
to detect the insertion of a cassette tape (not shown) thereinto and to be
actuated by electric power supplied from a (TAPE+B) terminal 12 to the
tape deck 11 through a transistor 13. The collector of the transistor 13
is connected with a drive motor 14 and plunger 15 in the tape deck 11. The
plunger 15 is connected with a head drive mechanism 16 which in turn is
connected with a head 17. On powering on, a head holding latch (not shown)
in the head drive mechanism 16 is actuated to hold the head 17 in contact
with the tape. Playback signals outputted from the head 17 are fed to a
radio/tape output switching circuit 22 through an equalizer circuit 21 and
then outputted from a speaker 24 through an amplifying circuit 23.
The emitter of the transistor 13 is connected with the (TAPE+B) terminal 12
through a drive resistor 26 while the base thereof is connected to the
emitter through a resistor 29 and also to the collector of a transistor 28
through a drive resistor 27.
The emitter of the transistor 28 is grounded with the base thereof being
grounded through a resistor 31. The base of the transistor 28 is also
connected with the interrupt signal output terminal of a microcomputer 34.
The interrupt signal outputted from the interrupt signal output terminal
is a negative logic (active "L") signal which is inputted to the base of
the transistor 28 and also to the radio/tape output switching circuit 22.
The radio/tape output switching circuit 22 selects either the cassette
tape signal or the radio reception signal, depending on the logical level
of the interrupt signal 33.
In the apparatus, the radio receiver further comprises a radio receiving
circuit 37 which includes various conventional circuits such as a
high-frequency amplifier, a local oscillator, a mixer, an intermediate
frequency amplifier, a detector, a noise killer, a multiplexer and so on.
The radio receiving circuit 37 provides radio waves containing FM
broadcast signals and the like received by an antenna 38 to the radio/tape
output switching circuit 22 and at the same time feeds data multiplexed
with the FM broadcast signals to a data demodulating circuit 39. The data
demodulating circuit 39 demodulates the data, the demodulated data being
outputted therefrom to the microcomputer 34.
On operation, the electric power is applied to the transistor 13 through
the (TAPE+B) terminal 12 when a cassette tape is inserted into the tape
deck 11 through its tape inlet (not shown). Since at this time, the active
"L" interrupt signal 33 from the microcomputer 34 is in a "H" state in the
tape signal prefered mode, the transistors 28 and 13 are also turned on to
energize the drive motor and plunger 14, 15. At the same time as the drive
motor 14 is actuated, the head holding latch of the head drive mechanism
16 is actuated to bring the head 17 into contact with the tape. Tape voice
signals read out from the cassette tape are supplied to the radio/tape
output switching circuit 22 through the equalizer circuit 21.
When the radio/tape output switching circuit 22 senses the tape voice
preferential mode "H" in the interrupt signal 33, the circuit 22 selects
the tape voice signals from the equalizer circuit 21 which in turn are
outputted therefrom to the amplifying circuit 23 to drive the speaker 24.
If the traffic or emergency information signals multiplexed with the FM
broadcasting signals are received during such a playback of tape voice
signals, these multiplexed signals are demodulated by the data
demodulating circuit 39 after being received by the radio receiving
circuit 37 through the antenna 38. The demodulated signals are received by
the microcomputer 34 which in turn changes the interrupt signal 33 from
"H" to "L". Thus, the transistors 28 and 13 are turned off to shut off the
power to the drive motor and plunger 14, 15. At the same time as the drive
motor 14 is stopped, the head drive mechanism 16 is unlatched to move the
head 17 away from the tape.
As the interrupt signal 33 is changed to "L", the system is switched from
the tape voice prefered mode to the radio voice prefered mode. In other
words, the radio/tape output switching circuit 22 selects the radio
receiving circuit 37 to cause the received traffic or emergency
information signals to be output through the speaker.
On termination of the transmission of traffic or emergency information
signals, this is sensed by the microcomputer 34 which changes the
interrupt signal 33 back to "H" so that the tape voice prefered mode will
be selected.
FIGS. 3 and 4 illustrate the relationship between tape, capstan and pinch
roller in the tape desk 11. In the tape voice prefered mode, the head
holding latch of the head drive mechanism 16 (FIG. 1) is held by the
plunger 15 (FIG. 1) such that the tape 43 is nipped between the pinch
roller 41 and the capstan 42, as shown in FIG. 3. This will be referred to
as the "pinching-on state".
In the radio voice prefered mode, the tape 43 is released between the pinch
roller 41 and the capstan 42 as shown in FIG. 4 since the plunger 15 is
deenergized. This will be referred to as the "pinching-off state".
In the related art radio receiver with the tape deck, thus, both the drive
motor and plunger 14, 15 are deenergized when the system is shifted to the
radio voice prefered mode due to the interrupt caused by traffic or
emergency information signals. If the traffic or emergency information
signals are unstably received by the radio receiver in a bad radio wave
reception area such as between mountains, the interrupt signal 33 from the
microcomputer 34 will be frequently changed from "H" to "L" or vice versa.
Thus, the plunger 15 will be frequently energized and deenergized. This
results in frequent repetition of the pinching-on and pinching-off states.
As a result, mechanical noise will be undesirably generated and the tape
will eventually be damaged.
It is therefore an object of the present invention to provide an improved
radio receiver with tape deck which can prevent the occurrence of
undesirable mechanical noise and also tape damage due to the frequent
switching between the radio and tape prefered modes.
SUMMARY OF THE INVENTION
To this end, the present invention provides a radio receiver comprising a
tape deck having (a) a drive motor for driving a cassette tape; (b) a
roller-capstan mechanism including a pinch roller and a capstan, the
mechanism being adapted to guide the cassette tape nipped between the
pinch roller and capstan on recording and reproducing of audio signals to
and from a cassette tape; (c) a head brought into contact with the tape to
record and reproduce the audio signals when the tape is nipped between the
pinch roller and the capstan; (d) a plunger for actuating a head holding
latch to move the pinch roller to a pinching-on state in which the tape is
nipped between the pinch roller and the capstan when the plunger is
energized and for releasing the head holding latch to move the pinch
roller to a pinching-off state in which the tape is released between the
pinch roller and the capstan when the plunger is deenergized, and the
radio receiver further comprising (e) a radio receiving circuit for
receiving broadcast waves including interrupting signals such as traffic
and emergency information signals; (f) a demodulating circuit for
demodulating the broadcasted waves received by the radio receiving
circuit; (g) an interrupt signal detecting circuit for detecting the
interrupt signal from the signals demodulated by the demodulating circuit;
(h) an output switching circuit for outputting radio voice signals from
the radio receiving circuit when audio playback signals are outputted from
the tape deck and if any interrupt signal is detected by the interrupt
signal detecting circuit; and (i) a first power terminal for supplying
electric power to the plunger in the event of a cassette tape being loaded
into the tape deck, irrespective of the state of the output switching
circuit.
In such an arrangement, the plunger is maintained energized even if the
system is switched to the radio voice signal output mode by the detection
of an interrupt signal. Thus, the pinch roller and capstan will not be
frequently moved into contact and non-contact with the tape even if the
system is frequently switched from the tape playback mode to the radio
voice signal output mode and vice versa. This can prevent the occurrence
of mechanical noise and also tape damage.
In one aspect of the present invention, a microcomputer may be used as the
interrupt signal detecting circuit.
In another aspect of the present invention, the first power terminal may be
powered on only when the cassette tape is loaded into the tape deck.
In still another aspect of the present invention, the drive motor may be
connected with the power supply through a second power terminal distinct
from the first power terminal.
In a further aspect of the present invention, the second power terminal may
be connected with the power supply only when the cassette tape is loaded
into the tape deck and an interrupt signal is not detected.
In a further aspect of the present invention, the radio receiver may
further comprise (j) a first transistor maintained "OFF" when it does not
receive an interrupt signal from the interrupt signal detecting circuit,
(k) a second transistor turned on when the first transistor is in its
"OFF" state and a voltage is applied to the first power terminal, and (l)
a third transistor turned on when the second transistor is turned on,
whereby the drive motor can be energized through the second power terminal
when the third transistor is in its "ON" state.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram illustrating one embodiment of a radio receiver
with tape deck constructed in accordance with the present invention.
FIG. 2 is a block diagram illustrating a radio receiver with tape deck
constructed in accordance with the related art.
FIG. 3 illustrates a pinching-on state in the tape deck.
FIG. 4 illustrates a pinching-off sate in the tape deck.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows one embodiment of a radio receiver with tape deck constructed
in accordance with the present invention, in which parts similar to those
of FIG. 2 are denoted by similar reference numerals and some parts will
not be further described herein. The radio receiver comprises a (+B)
terminal 45 functioning as a second power terminal to which a power
voltage will be applied when a switch (not shown) is switched on. The (+B)
terminal 45 is connected with the emitter of the transistor 13 through the
drive resistor 26. The collector of the transistor 13 is connected with
the drive motor 14 of the tape deck 11. The base of the transistor 13 is
connected with the emitter of the same through the resistor 29 and also
with the collector of the transistor 28 through the drive resistor 27.
A transistor 47 includes an emitter connected to ground and a base
connected to ground through a resistor 48 and also to the interrupt signal
output terminal of the microcomputer 34 through a resistor 49. The
interrupt signal 33 outputted from this interrupt signal output terminal
is a positive (active "H") signal which is also inputted to the radio/tape
output switching circuit 22. The radio/tape output switching circuit 22
selects one of the tape and radio voice modes depending on the logical
level of the interrupt signal 33 ("L" or "H"). The remainder of the
arrangement is similar to that of FIG. 2.
On operation, a when a cassette tape is inserted into the tape deck 11
through its tape inlet (not shown), a voltage is applied to the (TAPE+B)
terminal 12. When the switch of the radio receiver is switched on, a
voltage is applied to the (+B) terminal 45.
In the tape voice playback mode, the active "H" interrupt signal 33 from
the microcomputer 34 is at a "L" level. The transistor 47 is thus turned
off. As a result, the transistors 28 and 13 are turned on so that the
power is supplied from the (+B) terminal 45 to the drive motor 14 to drive
the tape. At this time, the plunger 15 is energized by the power from the
(TAPE+B) terminal 12 to hold the latch of the head drive mechanism 16 so
that the head 17 becomes ON. As a result, the relationship between the
tape, capstan and pinch roller in the tape deck 11 is shifted into the
pinching-on state shown in FIG. 3. Tape voice signals output from the
cassette tape are fed to the radio/tape output switching circuit 22
through the equalizer circuit 21.
Since the interrupt signal 33 is in its "L" state representing the tape
voice prefered mode, the radio/tape output switching circuit 22 selects
the tape voice signals from the equalizer circuit 21, which are then
amplified by the amplifying circuit 23 and outputted through the speaker
24.
If FM broadcasting waves multiplexed with traffic or emergency information
signals are transmitted during the tape voice playback, they are received
by the antenna 38. The received signals are then provided to the data
demodulating circuit 39 through the radio receiving circuit 37. After
being demodulated at the data demodulating circuit 39, the signals are
inputted to the microcomputer 34. On reception, the microcomputer 34
changes the interrupt signal 33 to the "H" state. The transistor 47 is
thus turned on and the transistors 28 and 13 are turned off. Therefore,
the drive motor 14 is deenergized and stopped. Unlike the prior art, the
plunger 15 is maintained energized by another power source distinct from
the power source for the driving motor 14. Therefore, the plunger 15 can
hold the head drive mechanism 16 latched to maintain the pinching-on state
shown in FIG. 3.
On the other hand, the system is shifted to the radio voice preferred mode
since the interrupt signal 33 has been changed to "H". The radio/tape
output switching circuit 22 selects the radio receiving circuit 37 such
that the traffic or emergency information signals received by the radio
receiving circuit 37 will be outputted from the speaker.
As the transmission of the traffic or emergency information signals is
terminated, this is sensed by the microcomputer 34 which changes the
interrupt signal 33 back to "L", such that the system will be again placed
in the tape voice prefered mode.
In accordance with the present invention, mechanical noise and impact on
the tape can be avoided even if the system is frequently switched from the
radio voice prefered mode to the tape voice prefered mode and vice versa,
since the pinching state is maintained throughout operation of the radio
receiver.
Although the present invention has been described as to the car radio
receiver, it is to be understood that the present invention is not limited
to the car radio receiver and may be similarly applied to conventional
domestic radio receivers or radio-cassette sets.
It is further to be understood that any suitable interrupt signal other
than the traffic or emergency information signals such as RDS may be used
in the present invention with similar advantages.
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